IGBTs are well known, and are shown, for example, in U.S. Pat. Nos. 6,683,331 and 6,707,111 both of which are assigned to the assignee of the present invention. Trench IGBTs are also described in copending application Ser. No. 11/230,969, filed Sep. 20, 2005 (entitled TRENCH IGBT WITH INCREASED SHORT CIRCUIT CAPABILITY in our names (IR-2949) the contents of which are incorporated herein by reference.
IGBTs are replacing power MOSFETs in highly capacitive load applications. Thus, plasma display panels used, for example, in projection TV receivers, act as highly capacitive loads in two basic circuits of sustain and energy recover. The IGBT is useful for such loads because of its higher current conduction capability and reduced conduction loss compared to the power MOSFET.
It would be desirable to further increase the current conduction ability and further reduce the conduction loss of an IGBT to enable the use of smaller chip area IGBTs for such capacitive loads.